1. Field of the Invention
The present invention relates to methods for diagnosing, monitoring and treating varices, and, in particular, to methods for non-invasive measurement of intra-variceal pressure and wall tension.
2. Description of the Related Art
Esophageal varices are one of the major causes of gastrointestinal bleeding. Varices are a frequent complication in patients with cirrhosis of the liver. Approximately 50,000 people in the United States are believed to suffer from esophageal varices each year. Of those, 35,000 people experience severe bleeding episodes, half of which are fatal.
Because of the severity of the outcome of gastrointestinal bleeding, many physicians favor prophylactic pharmacologic intervention with .beta.-blockers immediately after diagnosis of varices. Endoscopic sclerotherapy, balloon tamponade, pharmacologic therapy with vasopressives, nitrates, and somatostatin, transjugular intra-hepatic portal systemic hunts, and surgical portal systemic shunts are most frequently used once bleeding episodes are detected.
In order to determine which course of treatment is appropriate and to monitor the progress and effectiveness of that treatment, it is necessary to objectively evaluate and monitor the varices. Unfortunately, however, other than through direct observation of re-bleeding, or lack thereof, monitoring progress and recovery of varices is extremely difficult. Existing methods for monitoring varices, such as, esophagoscopy, have proven unreliable and inadequate.
While it is believed that variceal size, intra-variceal pressure and wall tension are the critical measures of the severity of an existing varix, it has not been possible to accurately and safely measure any of these variables in vivo. Known methods for measuring intra-variceal pressure involve actually puncturing the varix with a needle to take an intra-variceal pressure reading. This is a relatively high risk procedure with frequent complications, including severe bleeding. In addition, there are no known means for accurately determining the radius or the wall thickness of varices in vivo.
It is accordingly an object of this invention to overcome the disadvantages and drawbacks of the known art and to provide methods for safely and accurately diagnosing, monitoring and treating esophageal varices.
It is a further object of this invention to provide methods for non-invasive in vivo determination of variceal pressure, size and wall thickness.
It is a further object of this invention to provide methods for the in vivo measurement of variceal wall tension.
Further objects and advantages of this invention will become apparent from the detailed description of a preferred embodiment which follows.